1. Field of the Invention
The present invention relates to non-pull cord window blinds and more particularly, to a resistance adjusting device for the non-pull cord window blind.
2. Description of the Related Art
As to the general non-pull cord window blind, when the bottom beam is pulled downwardly, the lift transmission cord attached to the slats is pulled out by the bottom beam so as to escape from the cord rolling device gradually, until the slats are completely unfolded. In opposite, when the bottom beam is pushed upwardly, the upward pushing force applied to the bottom beam counteracts the weight of the bottom beam and all the slats, enabling the cord rolling device to roll up the lift transmission cord successfully, so that the slats can be folded up stably. However, no matter the bottom beam is in the process of being pulled downwardly or pushed upwardly by an external force, once the external force is relieved, the slats will not be easily fell down or folded up, but able to be stopped at any height at any time because of the appropriate resistance provided by a resistance device of the cord rolling device to the lift transmission cord.
For adapting to different usage requirements, the resistance provided by the resistance device to the lift transmission cord sometimes needs to be adjusted. However, in the aforesaid prior art, the user has to disassemble the whole cord rolling device before adjusts the resistance device and assemble the cord rolling device after the adjustment, that is very inconvenient in operation. Besides, many times of disassembly and assembly may affect the assembly accuracy of the inner members of the cord rolling device.